1. Field of the Invention
The present invention relates to a fastening element for attaching plate-shaped boards and including a large-surface clamping member, a hollow stem projecting from the clamping member and having a bore opening at the clamping member for receiving an expansion member for an anchoring member with which a plate-shaped board is secured to a constructional component, and a shaped member attached to the clamping member with a strap for closing the bore by being inserted therein.
2. Description of the Prior Art
Insulation materials, in particular, insulation boards are used for heat insulation and partially also for noise insulation of walls and ceilings. Conventionally, the insulation boards are secured to a raw masonry. For securing the plate-shaped insulation materials, fastening elements, which have a large-surface, flat clamping plate from which a stem projects, are used. The stem extends into the insulation board. The fastening element is secured to the masonry primarily with a dowel-like or nail-like anchoring member that forms an extension of the stem. The dowel-like anchoring member is inserted in a pre-drilled bore formed in the masonry and in anchored in the masonry bore by being expanded. A nail-like anchoring member is directly driven into the masonry, without preliminarily forming a bore in the masonry. A bore formed in the stem and opening into the clamping member insures access for an expansion screw or a similar expansion member used for expanding the dowel-like member or to a nail-like member. After the masonry is covered with the insulation material plaster is applied.
German Utility Model DE-U-91 03 388 discloses a fastening element of a type described above for securing a plate-shape insulation material to a masonry and in which a closing member is provided for the bore accessible from the clamping plate. The closing member prevents penetration of the plaster into the bore. The closing member may have different forms, e.g., the closing member can be formed as a plug-like member that, after being form-lockingly inserted in an annular groove, is retained on the bottom of the bore. The drawback of the fastening element disclosed in the German Utility Model consists in that the bore is not sealingly closed. Therefore, a complete seal is not provided which can result in heat losses and in discoloration of the plaster. An expansion screw or an expansion nail-like member, with such fastening element, is not adequately protected from moisture. The closing member is connected with the clamping plate by a thin strap. During mounting, often, the closing member is in the way and need be kept by a worker away from the bore. During mounting, a large number of fastening elements need be kept in a box, and the closing members, which are connected to respective clamping plates by straps, can interlock with each other or with the clamping plates. Upon placing the boxes in a transporting receptacle or during the removal of the fastening elements, the straps can be torn. As a result, some of the fastening elements would remain without the closing members, and respective bores could not be closed.
Accordingly, an object of the present invention is to eliminate the drawbacks of fastening elements of the prior art.
Another object of the present invention is to provided a fastening element that can be easily handled and accessed.
A further object of the present invention is to provide a fastening element in which the opening in the clamping plate can be sealingly closed so that a vapor barrier is provided, and the penetration of moisture into the bore is prevented.
A still further object of the present invention is to provide a fastening element which would insure an easy handling of the closing member.
Also, an object of the present invention is to provide a fastening element in which interlocking of the closing member with the clamping plate or member and the separation of the closing member therefrom is prevented.